Current cube tap



Mmh 15, 3%@ D. B. MILLER 323,96

CURRENT CUBE TAP Filed Nov. 6, 15,164 3 Sheets-Shea?l 2 INVENTORA .QAM/fMILLER ATTORNEY March 15, 1966 D.B.M1LLER CURRENT CUBE TAP 3Sheets-Sheet 3 Filed Nov. 6, 1964 INVENTOR.

DAN/z 6. M/msf? ATTORNEY United States Patent O 3,241,096 CURRENT CUBETAP Daniel B. Miller, Providence, RJ., assignor to InternationalTelephone and Telegraph Corporation, Nutley, NJ., a corporation ofMaryland Filed Nov. 6, 1964, Ser. No. 409,376 8 Claims. (Cl. 339-157)This invention relates to current taps such as cord connectorsconvenience outlets and cube taps having male prongs for insertion in aconvenience outlet and more particularly to a current tap with a minimumof molding material and contacts of thin `strip material of economicaldesign. The particular design of this invention enables the use of acontact of thin and narrow strip material wherein two strips serve forcontacts for a plurality of attachment plugs. In addition the design ofthe molded insulating body is such that a minimum of molding material isused.

The principal object of this invention is to provide a current tap witha novel contact of thin and narrow strip material, two of the contactsserving to receive the prongs of a plurality of attachment plugs.

Another object o-f this invention is to provide a current tap which isdesigned for the most economical construction with a minimum of moldingmaterial used therein.

Another object of this invention is to provide a current tap with acontiguration that lends itself, in virtue of the fact that the majoraxes of all female contacts are parallel to conventional moldingtechniques, such that manual or automatic loading of the mold issimplied, and also the construction of the mold, being more simple, iseconomical, both vas to construction and maintenance.

A feature of this invention is a current cube tap comprising a moldedbody of resilient insulating material, the molded body comprising afirst pair of parallel plug receivable openings disposed on a tirst sideof the body, second and third pairs of parallel plug receivable openingsdisposed on the side opposite its first side, the second and third pairsof openings being spaced from the axis of the rst pair on both sides ofthe iirst pair. The body has a recess in the center portion of the bodyalong substantially the length thereof. A pair of parallel contacts aredisposed in the insulating body on each side of the recess and inadjacent relationship to the pairs of parallel plug receivable openings,each of the contact strips comprising at one end thereof a U-shapedchannel for receiving connector wire, three elongated receptacles withangular ends formed by upper and lower portions of the contact stripwhich are spread apart to receive the blades of the plug. The upper andlower portions of each end receptacle has an offset tab in the centerthereof to form a cooperating tapered arrangement for the plug blade,the upper and lower portions of the center receptacle having offset tabsin the center thereof and disposed in a direction opposite the tabs ofthe end receptacles, the side of each receptacle opposite each tabhaving a recess substantially equal to the length and width of the tabfrom which recess the top is punched and the center receptacle of eachcontact strip being disposed adjacent the first pair of openings and theend receptacles being disposed adjacent the second and third pair ofopenings for receiving therein the blades of a plug.

The above-mentioned and other features and objects of this inventionwill become more apparent by reference to the following descriptiontaken in conjunction with the accompanying drawings, in which:

FIGURE 1 is a plan view of the current tap of this invention;

FIGURE 2 is a plan View of the side opposite to that shown in FIGURE 1;

. FIGURE 3 is an end view of the current tap;

FIGURE 4 is a cross section view along line 4 4; FIGURE 5 is a crosssection view along line 5 5; FIGURE 6 is a cross section View along line6 6; FIGURE 7 is another end view of the current tap; FIGURE 8 is anelevation view of one embodiment of the contact strip;

FIGURE 9 is an end view of the contact strip of FIGURE 8;

FIGURE 10 is a plan View of the contact strip of FIGURE 8;

FIGURE 11 is a cross section View along line 11 11;

FIGURE 12 is an elevation view of another embodiment of the contactstrip;

FIGURE I3 is an end view of the Contact strip of FIGURE 12;

FIGURE 14 is a plan view of the contact strip of FIGURE 13; and

FIGURE 15 is a cross section view along line 15-15.

With reference to FIGURES 1 through 7 there is shown a current tap ofthis invention, which comprises a molded body 1 of insulating material.On one side of the molded insulating body which has a substantiallyrectangular conti-guration, there is shown a pair of parallel openings 3disposed in approximately the center of the molded body from the end 4thereof to the point 5 where a taper begins in the body and extends downto the narrow end 6 o-f the plug where the connector wire 7 enters thetap. Each pair of parallel sides at this end are tapered towards thewire end. The parallel openings 3 are disposed apa-rt a sutlicientdistance -to receive the blade of a standard commercial attachment plug.On the side 8 which is diametrioally opposite to the side 2 there isshown second and third pairs 9 and 1t), of parallel openings forreceiving the blade of a plug attachment which are the same as theparallel openings 3 described above` Parallel openings 9 and 10 arespaced apart from each other and are on opposite sides of the axis ofthe parallel openings 3. The sides 11 and 12 which join the sides 2 and8 are slightly curved as are also sides 2 and 8. Sides 11 and 12 Iarecurved also along the long axis lfrom the end surface 4 and continuebeyond the paper start point 5 `and then curve sharply towards the endsurface 6 of the tap. As shown in the cross section view of FIGURE 4 theparallel plug openings extend within the tap to a point near theopposite side of the tap to allow for insertion of the 4mating bladeplug. Disposed Within the center portion of the body of the tap 1 is arectangular cavity 15 which extends along the major portion of the bodyand partially Within the tapered .portion` It will be observed that thewall thickness is substantially uniform for the top and bottom and forthe side walls, the wall thickness of the side walls being greater topermit the insertion of the contact strips. The top and bottom walls 16and 17 can be seen to be thinner than the side walls 18 and 19. Theadvantage iered by the cavity is that less molding material is re-[uired .and the uniform wall thickness insures more uniorm and fastercooling. Each of the parallel openings i, 9 and 10 have tapered edges 20to allow for easy inertion of the blade of the attachment plug. Thecorilector cord enters the tap at the end 6 and divides into wo channels21 and 22 which lead to parallel channels b3 and 24 in which aredisposed lthe contact strips.

The contact strip will be described with reference to F`IGURES 8 to 11.Two of the contact strips shown in ,hese figures are required for eachcurrent tap, one on :ach side of the long axis as shown in FIGURE where:ach contact strip is numbered 25. The contact strip Z5 is linear andcomprises substantially an upper portion I6 and .a lower portion 27,both portions, being formed )ut of -the same st-rip material and `bothbeing attached ',ogether at various places where there has been noslitting :hrough for formation of the receptacle portions and the :ndtabs. At one end of the contact strip is a U-shaped :ab 30 which isformed out of one tab element 31 and two :ab elements 32 on the sideopposite tab element 31 with :he connecting base section 33. The tab 30receives one of the connecting wires for Athe current tap and when thewire is properly in position therein tab elements 31 and 32 are bentover the wire .and securely crimped therein to hold the wire securely inplace. Each contact strip Z5 contains 3 receptacles 35 which are in theshape substantially rectangular wi-th angular ends 36, the middleportions 37 of the receptacles being curved inwardly to provideappropriate spring tension and wiping contact on the blades of theattachment plug to be inserted therein. Each end receptacle 35 has 2tabs 38 and 39. Tab 38 is .approximately in the center of 1thereceptacle 35 .and extends from the upper portion 26 of the contactstrip. At the top the tab 38 is offset slightly as is shown at 40 toprovide a 4tapered entrance as a guide for the blade of the attachmentplug. Tab 39 extends upwardly from the lower portion 27 of the contactstrip and offset :as shown at 41 so that there is provided with thecooperating tabs 38 and 39 offset as shown at 40 and 41, an entrance forthe blade of the attachment plug which then fits into the receptacle 35and is securely retained therein by the spring action of the linwardlycurved walls 37 of the receptacl-e 35. The same type of tab is :repeatedin the opposite end receptacle 35 of the contact strip. Thus there isprovided receptacles with offset tabs extending upwardly so that twosets of bla-des can enter from the top goin-g down into the endreceptacle through parallel -openings 9 and 10. The center receptacle 35has a similar arrangement with inwardly curving walls but here the tabsextend downward from lthe bottom portion 37 and the top portion 26 4asshown at 45 and 46 and are offset in .a similar Imanner to the tabs 38,39 to provide a tapered entrance into the receptacle. The centerreceptacle 35 is disposed to receive the blades `of a plug enteringthrough parallel openings 3. It will be noted that on each portion upperand lower of contact strip 35 there is a recess 50 from which .acorresponding tab 38, 39, 45 or 46 has been stamped. By virtue of thisarrangement also it can be seen that 4the tab element 31 of the U-shapedtabe has been stamped out of the similar recess 51 from the adjoinin-gcontact strip. This particular design .as illustrated here provides anovel contact strip on 1A inch centers wher-e no waste of materialoccurs :and the same contact strip is used to provide receptacles for 3blades of the attachment plug. Therefore by using 2 of these contactstr-ips 25 it is possible to provide .the contact strips for the currentcube tap of this invention which can accommodate three `attachmentreceptacles. In the molding process the contact strips 25 with theconnector cord 7 securely crimped in the end tabs 30 are placed inposition in the -rnold and molding insulating material is then injectionmolded about the contact strips and the wire. The preferred insulation`material is polyvinyl chloride, though it is understood that othersuitable molding in- .sulating material may be used. The recesses 55 inthe contact strips are semi-circular portions of holes punched in thecontact strips to facilitate the shearing of'rr of the individualcontact strips from the strip sheet which is processed through thepunching and shearing machines.

Another embodiment of the contact strip is shown in FIGURES 12-15inclusive. As in t-he first embodiment of -the contact strip two Iof thecontact strips shown in these figures are required for each current tap,one on each side of the long axis as shown in FIGURE 5. The contactstrip `66 of the second embodim-ent is linear and comprises threeportions, an upper portion, .a middle porti-on 62 and a lower portion63, :all three portions being formed out of the same strip material andall being attached together at those places, such as 64, where there hasbeen no slitting through for formation of the receptacle portions 65, 66and `67. At one end of the cont-act strip is the U-shaped tab 30 whichis similar to the tab described in connection with the first contactstrip and is formed out of one tab element 31 and two tab elements 32 onthe side opposite tab element 31 with the connecting base section 33.The three receptacle portions 65, 66 and 67 are substantiallyrectangular with angular ends 69, the middle portions 70 of 4thereceptacles being curved inwardly to provide appropriate spring tensionand wiping contact on the blades of the attachment plug to be insertedtherein. Each middle portion 70 and angular portion 69 is curvedoutwardly as shown a-t 71 to provide a tapered entrance as a guide forthe blade of the attachment plug. It will be observed that the outerportions are curved in one direction .and the middl-e portion is curvedin the opposite direction. As shown more particularly in FIG- URE 15 theattachment plug blade when inserted will move downward or upward, as thecase may be on curved surfaces 71. In this embodiment as in the firstembodiirnent, the receptacles vot two contact strips, disposed in lthe.molded body, will .accommodate two sets of Vattachment plug bladesentering from one side and one set of attachment plug blades enteringfrom the other side.

While I have described above the principles of my invention inconnection with specific apparatus it is to be clearly understood that-this description is ymade only by Way'of example and not as alimitation to the sc-ope of my invention as set forth in the objectsthereof and in the accompanying claims.

I claim:

1.. A current cube tap comprising a molded body of resilient insulatingmaterial, said molded body cornprising a first pair of parallel plugreceivable openings disposed on a first side of said body, second andthird pairs of parallel plug receivable openings disposed on the sideopposite said first side, said second and third pair of openings beingspaced from the axis of said first pair on both sides of said rst pair,a recess in said body along substantially the length thereof, a pair ofparallel contact strips disposed in said body, one of said contactstrips on each side of said recess and in adjacent relationship to saidpairs of parallel plug receivable openings, each said contact striphaving formed therein a plurality of longitudinal slits, the slitsdefining at the sides thereof contact strip portions, said portionsfurther being offset, in opposite directions, with reference to thegeneral plane of the contact strip, and forming therebetween, lateral ofsaid contact strip, a series of at least three receptacles to receivethe connector blades of the plug, said receptacles having angular endand side elements formed by said oppositely offset portions, said sideelements lying substantially parallel to said general plane save forslight curvature of each toward the said general plane, said sideelements each having a plurality of integral guides, one above the otherand transverse to the axis of said cube tap, to facilitate reception ofthe plug blades, the center receptacle of each said contact strip beingdisposed adjacent said first pair of openings and the end receptaclesbeing disposed adjacent said second and third pair of openings forreceiving therein the blades of the plug.

2. A current tap according to claim 1 wherein said recess is asubstantially rectangular cavity extending along the long axis of saidbody and each pair of parallel sides have uniform wall thickness.

3. A current cube tap comprising a molded body of resilient insulatingmaterial, said molded body comprising a first pair of parallel plugreceivable openings disposed on a first side of said body, second andthird pairs of parallel plug receivable openings disposed on the sideopposite said first side, said second and third pair of openings beingspaced from the axis of said first pair on both sides of said firstpair, a recess in said body along substantially the length thereof, apair of parallel contact strips disposed in said body, one of saidcontact strips on each side of said recess and in adjacent relationshipto said pairs of parallel plug receivable openings, each said contactstrip having formed therein a plurality of longitudinal slits, the slitsdefining at the sides thereof upper and lower portions, said upper andlower portions further being offset in opposite directions, withreference to the general plane of the contact strip, and formingtherebetween three receptacles to receive the connector blades of theplug, said receptacles having angular end and side elements formed bysaid side elements lying substantially parallel to said general planesave for a slight curvature of each toward said general plane, the upperand lower portions of each end receptacle having an offset tab in thecenter thereof, the upper and lower portions of the center receptaclehaving an offset tab in the center thereof and disposed in a directionopposite said end receptacle tabs, said center receptacle of each saidcontact strip being disposed adjacent said first pair of openings andsaid end receptacles being disposed adjacent said second and third pairof openings for receiving therein the blades of the plug.

4. A current cube tap comprising a molded body of resilient insulatingmaterial, said molded body comprising a first pair of parallel plugreceivable openings disposed on a first side of said body, second andthird pairs of parallel plug receivable openings disposed on the sideopposite said first side, said second and third pair of openings beingspaced from the axis of said first pair on both sides of said firstpair, a recess in said body along substantially the length thereof, apair of parallel contact strips disposed in said body, one of saidcontact strips on each side of said recess and in adjacent relationshipto said pairs of parallel plug receivable openings, said contact striphaving formed therein a plurality of longitudinal slits, the slitsdefining at the sides thereof upper and lower portions, said upper andlower portions further being offset, in opposite directions, withreference to the general plane of the contact strip, and formingtherebetween, lateral of said contact strip, three substantiallyelongated receptacles to receive the connector blades of the plugs, saidreceptacles having angular end and side elements formed by said upperand lower portions, said side elements lying substantially parallel tosaid general plane save for a slight curvature of each toward saidgeneral plane, the upper and lower portions of each end receptaclehaving an offset tab in the center thereof, the upper and lower portionsof the center receptacle having an offset tab in the center thereof anddisposed in a direction opposite said end receptacle tabs, the side ofeach receptacle opposite each said tab having a recess substantiallyequal to the length and width of said tab, said center receptacle ofeach said contact strip being disposed adjacent said first pair ofopenings and said end receptacles being disposed adjacent said secondand third pair of openings for receiving therein the blades of the plug.

5. A contact strip for a current cube tape having a plurality oflongitudinal slits, the slits defining at the sides thereof upper andlower portions, said portions further being offset, in oppositedirections, with reference to the general plane of the contact strip,and forming therebetween, lateral of said contact strip, threereceptacles to receive the connector blades of an attachment plug, saidreceptacles having angular end and side elements formed by saidoppositely offset upper and lower portions, said side elements lyingsubstantially parallel to said general plane save for a slight curvatureof each toward said general plane, the upper and lower portions of eachend receptacle having an offset tab in the center thereof, the upper andlower portions of the center receptacle having an offset tab in thecenter thereof and disposed in a direction oposite said end receptacletabs.

6. A contact strip for a current cube tap having a plurality oflongitudinal slits, the slits defining at the sides thereof upper andlower portions, said upper and lower portions further being offset, inopposite directions, with reference to the general plane of the contactstrip, and forming therebetween, lateral of said contact strip, threesubstantially elongated receptacles to receive the connector blades ofan attachment plug, said receptacles having angular end and sideelements formed by said oppositely offset upper and lower portions, saidside elements lying substantially parallel to said general plane savefor a slight curvature of each toward said general plane, the upper andlower portions of each end receptacle each having an offset tab in thecenter thereof, both said tabs disposed in the same direction, the upperand lower portions of the center receptacle each having an offset tab inthe center thereof and disposed in a direction opposite said endreceptacle tabs.

7. A current cube tap comprising a molded body of resilient insulatingmaterial, said molded body comprising a first pair of parallel plugreceivable openings disposed on a first side of said body, second andthird pairs of parallel plug receivable openings disposed on the sideopposite said first side, said second and third pair of openings beingspaced from the axis of said first pair on both sides of said firstpair, a recess in said body along substantially the length thereof, apair of parallel contact strips disposed in said body, one of saidcontact strips on each side of said recess and in adjacent relationshipto said pairs of parallel plug receivable openings, each said contactstrip having formed therein a plurality of longitudinal slits, the slitsdefining at the sides thereof upper, lower, and middle portions, saidupper, lower, and middle portions further being offset, in oppositedirections, with reference to the general plane of the contact strip,and forming therebetween, lateral of said contact strip, threereceptacles to receive the connector blades of the plugs, saidreceptacles having angular end and side elements formed by said upper,lower, and middle portions, said side elements lying substantiallyparallel to said general plane, said side elements of said receptaclesbeing curved outwardly to facilitate the entrance of said plug bladesand being curved inwardly to exert spring pressure upon said plugblades, the upper and lower portions of each said receptacle beingcurved in the same direction and the middle portion of said receptaclebeing spread apart from said upper and lower portions and curved in theopposite direction, said center receptacle of each said contact stripbeing disposed adjacent said first pair of openings and said endreceptacles being disposed adjacent said second and third pair ofopenings for receiving therein the blades of the plug.

8. A contact strip for a current cube tap having a plurality oflongitudinal slits, the slits defining at the sides thereof upper,lower, and middle portions, said upper, lower, and middle portionsfurther being offset, in opposite directions, with reference to thegeneral plane of the contact strip, and forming therebetween, lateral ofsaid contact strip, three receptacles to receive the connector blades ofan attachment plug, said receptacles having angular end and sideelements formed by said upper, lower, and middle portions, said sideelements lying substantially parallel to said general plane save foreach having slight curvatures, each being curved outwardly to facilitatethe entrance of said plug blades and being curved inwardly to exertspring tension upon said plug blades, the upper and lower portions ofeach said receptacle being curved in the same direction and the middleportion of said receptacle being spread apart from said upper and lowerportions and curved in the opposite direction.

References Cited by the Examiner UNITED STATES PATENTS Parajon 339-21 XWeiss 339-157 Gilbert 339-218 X Boardman 339-22 X Herman et al 339-61JOSEPH D. SEERS, Primary Examiner. 10 w. DONALD MILLER, Examiner.

5. A CONTACT STRIP FOR A CURRENT CUBE TAPE HAVING A PLURALITY OFLONGITUDINAL SLITS, THE SLITS DEFINING AT THE SIDES THEREOF UPPER ANDLOWER PORTIONS, SAID PORTIONS FURTHER BEING OFFSET, IN OPPOSITEDIRECTIONS, WITH REFERENCE TO THE GENERAL PLANE OF THE CONTACT STRIP,AND FORMING THEREBETWEEN, LATERAL OF CONTACT STRIP, THREE RECEPTACLES TORECEIVE THE CONNECTOR BLADES OF AN ATTACHMENT PLUG, SAID RE CEPTACLESHAVING ANGULAR END AND SIDE ELEMENTS FORMED BY SAID OPPOSITELY OFFSETUPPER AND LOWER PORTIONS, SAID SIDE ELEMENTS LYING SUBSTANTIALLYPARALLEL TO SAID GENERAL PLANE SAVE FOR A SLIGHT CURVATURE OF EACHTOWARD SAID GENERAL PLANE, THE UPPER AND LOWER PORTIONS OF EACH ENDRECEPTACLE HAVING AN OFFSET TAB IN THE CENTER THEREOF, THE UPPER ANDLOWER PORTIONS OF THE CENTER RECEPTACLE HAVING AN OFFSET TAB IN THECENTER THEREOF AND DISPOSED IN A DIRECTION OPPOSITE SAID END RECEPTACLETABS.